Running a Crystal Reports ReportDocument object or a RAS ReportClientDocument object in a multithreaded .NET application will generate one or both of the following exceptions:
- ThreadStateException was unhandled
- Current thread must be set to single thread apartment (STA) mode before OLE calls can be made. Ensure that your Main function has STAThreadAttribute marked on it. This exception is only raised if a debugger is attached to the process.
- Windows OS all versions
- Visual Studio all versions
- Crystal Reports XI R2
- Crystal Reports 2008
- Crystal Reports for Visual Studio 2010
Reproducing the Issue
In Visual Studio create a child thread that instatiates a ReportDocument or ReportClientDocument object
- The ReportDocument and ReportClientDocument are marked safe for single threaded apartment model only.
- The ReportDocument and ReportClientDocument can only be safely accessed by the thread that created it, or the parent thread.
The apartment state property of the thread needs to be set to single threaded apartment (STA) for example:
Thread MyCrystalThread = new Thread(new ThreadStart(RunReport));
Multi-Threaded CR RAS error 13 hangs desktop CR for VS CRforVS thread multithreading , KBA , BI-DEV-NET , BI Software Development Kits (SDKs) - .NET or Other , How To